Chapter 9 - Sanitary Sewer Plan

Savage 2040 Comprehensive Plan Chapter 9: Sanitary Sewer Plan

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CHAPTER 9: SANITARY SEWER PLAN

BACKGROUND

The Sanitary Sewer Plan evaluates the adequacy of the existing sanitary sewer system,

projects sanitary sewer flows from future development, and recommends future

improvements to accommodate future flows. This plan is used by both the City locally

and the Metropolitan Council regionally for long-term planning of sanitary sewer

infrastructure.

In 1984, the City of Savage prepared a Comprehensive Sanitary Sewer Plan describing

the expansion of the municipal sewer system to serve the ultimate development of the

City. In 2004, the City submitted an updated sewer plan that was found to meet the

Metropolitan Council’s Tier II requirements. Most recently, in 2009, the City submitted

another update to the sewer plan that was also found to meet the Metropolitan

Council’s requirements.

The initial sanitary sewer trunk for the City was constructed in the 1970s and was sized

to accommodate the urbanization of that portion of the City lying generally east of

CSAH 27 (Dakota Avenue). The trunk system has since expanded to serve most of the

City, with the exception of the far southwest corner. Figure 9-1 illustrates the existing

service area, and Figure 9-2 illustrates the locations of City sanitary sewers and lift

stations and Metropolitan Council Environmental Services (MCES) interceptor sewers.

Currently, the City has approximately 134 miles of sanitary sewer lines providing

services to households and businesses. Trunk sewers and lift stations collect the

wastewater and deliver it to the MCES interceptor sewers. The primary MCES

interceptor sewer serving the City of Savage is the Savage Interceptor. The smaller

Southeast Sanitary District flows into Burnsville and into the Southwest Interceptor.

These two MCES Interceptors flow north and eastward, where they connect with the

MSB 7030 Interceptor, which delivers the waste to the MCES Seneca Wastewater

Treatment Plant in Eagan. A small portion of the City, identified as the Southwest

Sanitary District, flows into the Prior Lake Interceptor and ultimately to the MCES Blue

Lake Wastewater Treatment Plant in Shakopee.


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EXISTING SANITARY SEWER SYSTEM

Sanitary Sewer Service Area

Except for the far southwestern portion of the city, all of Savage has access to public

sanitary sewer. The trunk sanitary sewer system is planned to be expanded to provide

service to the unserved areas. Because the entire City is located within the

Metropolitan Urban Service Area (MUSA), MCES will provide regional collection and

treatment for all future development within the city.

The City sanitary sewer system has been divided into four (4) main districts and thirty-

eight (38) sub-districts to assist with flow allocations and capacity analysis. The

existing districts and sub-districts are shown in Figure 9-1.

Intercommunity Flows

The City has several intercommunity sanitary sewer flows with neighboring

communities. These service areas are summarized in Table 9-1 below.

Table 9-1. Intercommunity Flows

Neighboring

Community Flow INTO Savage Flow OUT OF Savage

Burnsville 30 homes

(Rose Bluff) N/A

Prior Lake N/A 120 homes, 1 business

(Cates Lake, Country Court)

Gravity Sewers

The system’s gravity sewers include 8-inch through 36-inch diameter pipe. Much of

the system is polyvinyl chloride (PVC) pipe, although other pipe materials include

reinforced concrete (RCP), vitrified clay (VCP), ductile iron (DIP), and centrifugally cast

fiberglass-reinforced polymer mortar (CCFRPM). The trunk gravity sewers are shown

in Figure 9-2.


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Figure 9-1: Existing Sanitary Sewer Districts


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Existing Wastewater Flows

The MCES measures wastewater flows within the City of Savage utilizing flow meters.

Meters M405 and M406 measure the majority of the flow generated in the City.

M405 measures the wastewater flow generated in the Southeast district, and M406

measures the wastewater flow generated in both the West and East districts.

Historical flow data from these meters is shown in Tables 9-2 and 9-3.

The total average daily flow generated in Savage from 2013-2017 was approximately

2.16 million gallons per day (MGD). This total is slightly greater than the sum of the

average daily flows below because the wastewater from sub-districts SW-1 and SW-2

flows unmetered into the City of Prior Lake.

Table 9-2. M405 Historical Wastewater Flow

Year Average Daily Flow

(MGD)

Peak Flow

(MGD) Peak Factor

2013 0.246 0.612 2.48

2014 0.252 0.703 2.79

2015 0.248 0.613 2.47

2016 0.248 0.606 2.45

2017 0.246 0.623 2.53

5-Year Average 0.248 0.631 2.54

Table 9-3. M406 Historical Wastewater Flow

Year Average Daily Flow

(MGD)

Peak Flow

(MGD) Peak Factor

2013 1.815 5.599 3.09

2014 1.833 5.776 3.15

2015 1.785 5.723 3.21

2016 1.870 6.042 3.23

2017 1.905 4.701 2.47

5-Year Average 1.841 5.568 3.03


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Existing Lift Stations

The City sanitary sewer system includes fourteen (14) lift stations. The installation

years, pumping capacities, peak hourly flows, and existing residual capacities of each

lift station are provided in Table 9-4. The firm pumping capacity, which should equal

or exceed the peak hourly sanitary flow, is the capacity of the station with its largest

pump out of service. The firm capacity for the lift stations equipped with more than

two pumps was calculated using SewerCAD V8i, a sewer modeling software. The

location of each lift station is indicated in Figure 9-2.

Table 9-4. Existing Lift Station Summary

Lift Station Year

Built

No. of

Pumps

Individual Pump

Design Capacity

(gpm)

Firm Pumping

Capacity

(gpm)

Peak Flow

(gpm)

Residual

Capacity

(%)

139th St 1971 2 110 110 4 96

Natchez 1979 2 50 50 17 67

Utica 1979 3 275 350 203 42

Ottawa 1979 2 50 50 10 80

Hwy 13 1984 2 600 600 374 38

Deer Run 1985 2 100 100 9 91

River Bend 1988 3 1,000 1,700 438 74

Steiner 1992 2 720 720 281 61

Bunge 1992 2 150 150 115 23

Cty Rd 42 1993 2 1,000 1,000 264 74

154th St 1996 2 380 380 179 53

Downtown 2000 3 560 850 451 47

Oak Hills 2003 2 400 400 32 92

Big Sky 2017 3 1,040 2,300* 53 98

* Dual forcemains


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Existing Trunk Sewers

A trunk main is a sewer pipe having a diameter greater than eight (8) inches. It is

important to ensure that trunk mains are sized properly since they convey large

quantities of flow. Trunk mains throughout the City of Savage were identified, and

their capacities were analyzed with SewerCAD. The size, capacity, sub-district being

served by each trunk main, existing peak hourly flows, and existing residual capacities

are listed in Table 9-5. Residual capacities obtained from the SewerCAD model are

shown in Figure 9-3.

Table 9-5. Trunk Sewer Summary

Sub-District Diameter

(in)

Capacity

(gpm)

Peak

Flow

(gpm)*

Residual

Capacity

(%)

W-15 15 1,095 132 88

W-14 33 6,337 259 96

W-13 33 4,434 332 93

W-12 33 4,118 677 84

W-11 15 1,321 220 83

W-10 36 6,746 1,196 82

W-9 18 2,687 210 92

W-8 18 5,536 224 96

W-6 15 9,024 128 99

W-4 12 619 174 72

W-5 36 5,184 2,177 58

E-17 10 609 161 74

E-16 15 2,673 213 92

E-9 12 639 346 46

E-7 18 2,033 493 76

E-5 12 856 576 33

E-8 15 1,381 304 78

E-6 12 1,113 458 59

E-4 10 580 64 89

E-1 36 6,693 3,875 42

*Peak hourly flow in trunk mains includes all wastewater flows

collected in upstream sub-districts.


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Figure 9-2: Existing Sanitary Sewer System


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Figure 9-3: Existing Residual Capacity


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Individual Sewage Treatment Systems

Many homes in Savage are served by individual sewage treatment systems (ISTS), also

known as septic systems. As of October 2018, there were a total of 106 active ISTS

within the City. Two (2) of these systems have been identified as non-conforming and

are planned for repair or abandonment. Scott County administers the regulation and

oversight of these systems.

Connection to City utilities is governed by City Code Title 5, Chapter 53, excerpted

below. Generally, if a dwelling is located within 200 feet of a new sanitary sewer or

water main, the property owner must connect after receiving notification from the City

Clerk. If an ISTS was installed or replaced prior to the availability of public sewer

service then it may be allowed to continue in operation if the property owner obtains

a waiver from the City in accordance with Section 53.02.

§ 53.01 SEWER SERVICE CONNECTIONS.

(A) Connection required, notice. When property abuts or has access to any public street

or alley and a dwelling on the property is within 200 feet of the proposed construction

along which sewer mains have been constructed, the owner of any dwelling or

commercial establishment on the property shall connect with the sanitary sewer in

accordance with the provisions of this chapter within 90 days after the date of mailing

or delivering official notice to do so. The notice shall be given to the owner or occupant

in writing by the City Clerk on order of the Council.

Community Treatment Systems

There are no public or private community treatment system within the City of Savage.

All properties within the City are served by the public collection system or by ISTS.


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Figure 9-4: Individual Sewage Treatment Systems


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SEWAGE GENERATION RATES

The City of Savage’s zoning policy encourages development in “planned

developments.” These developments result in housing densities on the order of 2.5 to

11 units per acre. Table 9-6 displays the sanitary sewer generation rates used in this

Sanitary Sewer Plan. These generation rates are based on the existing land use

densities of the City of Savage.

Table 9-6. Assumed Sanitary Sewer Flows by Land Use Type

Land Use Average Flow

(gallons/acre/day)

Single Family Residential (SFR) 650

Med-Density Residential (MDR) 950

High-Density Residential (HDR) 1,250

Mixed Use 1,500

Commercial 800

Industrial & Office 800

Business Park 800

Institutional 800

Park 50

Historical flow meter data was used in conjunction with the assumed sewer generation

rates listed in Table 9-6 to allocate existing wastewater flows to each district and sub-

district. These flows were entered into the SewerCAD model to evaluate existing trunk

sewer capacity. The residual capacities obtained from modeling are displayed in

Figure 9-3. The assumed sewer generation rates shown in Table 9-6 were also

applied to future land use designations to project future wastewater flows.


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FLOW VARIATION FACTORS

To ensure that the sanitary sewer system is capable of handling flow fluctuations

throughout the day and during rainfall events, peak flow factors are applied based on

average flows. Pipes that serve smaller areas are more likely to experience larger

fluctuations in flow. Therefore, the peak factor decreases as average flow increases.

The MCES flow variation factors for sewer design are listed in Table 9-7 below. These

factors were used to calculate future peak hourly flows. Existing peak hourly flows

were calculated using the peak factors obtained from MCES meter data.

Table 9-7. MCES Flow Variation Factors for Sewer Design

Average Flow

(MGD)

Peak Hourly

Flow Factor

Average Flow

(MGD)

Peak Hourly

Flow Factor

0.00 to 0.11 4.0 1.90 to 2.29 2.8

0.12 to 0.18 3.9 2.30 to 2.89 2.7

0.19 to 0.23 3.8 2.90 to 3.49 2.6

0.24 to 0.29 3.7 3.50 to 4.19 2.5

0.30 to 0.39 3.6 4.20 to 5.09 2.4

0.40 to 0.49 3.5 5.10 to 6.39 2.3

0.50 to 0.64 3.4 6.40 to 7.99 2.2

0.65 to 0.79 3.3 8.00 to 10.39 2.1

0.80 to 0.99 3.2 10.40 to 13.49 2.0

1.00 to 1.19 3.1 13.50 to 17.99 1.9

1.20 to 1.49 3.0 18.00 to 29.99 1.8

1.50 to 1.89 2.9 Over 30.00 1.7


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PROJECTED POPULATION AND SANITARY SEWER FLOW

Projected Population

The Metropolitan Council projects populations and sanitary sewer flows for each

community in the Metropolitan Area. The Metropolitan Council’s population

projections for the City of Savage are listed in Table 9-8 below.

Table 9-8. Population Projections

Year Total Sewered

Population Households Employment Population Households Employment

2010 26,911 9,116 6,753 24,577 8,305 6,135

2020 33,400 11,600 8,100 31,070 10,790 7,480

2030 37,400 13,000 8,800 35,070 12,190 8,180

2040 41,100 14,300 9,400 38,770 13,490 8,780

The sewered population projections have been allocated to the MCES Meter Service

Areas within the City of Savage as listed in Table 9-9 below. The vast majority of

growth is expected to occur within Metershed M406.

Table 9-9. Projections by Meter Service Area & Interceptor

Meter M404 (Prior Lake)* M405 (Burnsville) M406 (MCES Lift Station in Savage)

Interceptor 7120 3-BV-39 8560

Year Popn. Hhds. Empl. Popn. Hhds. Empl. Popn. Hhds. Empl.

2010 324 120 5 3,524 1,305 10 20,729 6,880 6,120

2020 338 125 5 3,532 1,308 10 27,200 9,357 7,465

2030 351 130 5 3,542 1,312 10 31,177 10,748 8,165

2040 0 0 0 3,553 1,316 10 35,217 12,174 8,770

*The flows generated in SW-1 and SW-2, which contribute to the flow metered in M404, will be

rerouted to flow towards the Big Sky Lift Station. When this happens, the flows generated within

SW-1 and SW-2 will be metered by MCES Meter M406, instead of MCES Meter M404. This is

expected to occur between 2030 and 2040.


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Projected Wastewater Flows

Table 9-10 lists the projected total average wastewater flow for the City of Savage

from the MCES Water Resources Policy Plan (WRPP) and this Sanitary Sewer Plan.

The projections in this report are greater than the MCES projections since they rely on

flow estimates for each parcel of developable land rather than population growth.

Additionally, it is anticipated that flow generated in the Credit River West Sewer

District (CRWSD), located immediately south of Savage, will discharge to the Big Sky

lift station as indicated in the Big Sky Station Feasibility Study completed in 2016.

Thus, this flow was included in the future flow projections for the Western district. The

flow generated by the CRWSD is expected to be 0.7 MGD on average in 2040, based

on the capacity of an 18-inch trunk sewer.

Table 9-10. Total Average Wastewater Projections

Projection Source 2020 Projected

Flow (MGD)

2030 Projected

Flow (MGD)

2040 Projected

Flow (MGD)

MCES WRPP 2.35 2.54 2.71

Sanitary Sewer Plan 2.30 3.01 3.72

Future flow projections were divided by sewer district and are shown in Table 9-11.

Note that although there will be a minor increase in the wastewater generated in the

Southeast and Southwest districts given the projections shown in Table 9-9, this flow

increase is not perceptible in Table 9-11 since the average wastewater flows are

expressed in million gallons per day.

Table 9-11. Average Wastewater Projections by Sewer District

Sewer District 2020 Projected

Flow (MGD)

2030 Projected

Flow (MGD)

2040 Projected

Flow (MGD)

East 0.82 0.91 1.00

Southeast 0.25 0.25 0.25

Southwest 0.07 0.07 0.07

West 1.16 1.78 2.40


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PROPOSED SANITARY SEWER SYSTEM

The sanitary sewer system will require expansion to serve future development. The

proposed future sanitary sewer districts are shown in Figure 9-5 and the proposed

future sanitary sewer system is shown in Figure 9-6. The new trunk sewers were sized

and located based on the areas that the City expects to develop. The exact alignment

of the proposed trunk sewers and lift stations may change during the design phase of

each project. The purpose of these recommendations is to provide the City with an

overall plan for large infrastructure additions and replacements. Future wastewater

flows generated throughout the City of Savage were calculated using the assumed

sewer generation listed under Table 9-6 and future land use data provided by the

City. Recommended peak factors displayed in Table 9-7 were used to estimate future

peak hourly flows.

Lift Station Analysis

The SewerCAD model was used to evaluate the residual capacity of each lift station.

The peak flows and residual capacities of City lift stations are listed in Table 9-12

below. The majority of the lift stations are projected to have adequate capacity

through full build out development.

Table 9-12. Future Lift Station Capacity Analysis

Lift Station

Firm Pumping

Capacity

(gpm)

Future Peak

Hourly Flow

(gpm)

Residual

Capacity (%)

139th St 110 6 95

Natchez 50 22 56

Utica 350 280 20

Ottawa 50 13 73

Hwy 13 600 619 -3

Deer Run 100 12 88

River Bend 1,700 647 62

Steiner 720 410 43

Bunge 150 152 -2

Cty Rd 42 1,000 340 66

Downtown 850 632 26

Oak Hills 400 52 87

Big Sky 2,300* 2,141** 7

* Dual forcemains

** The Big Sky Lift Station has capacity for rerouted flows from SW-1 and SW-2, as

well as wastewater collected in the CRWSD. The future peak hourly flow reflects

these additions.


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As seen in Table 9-12, the future peak hourly flows at two lift stations (Hwy 13 and

Bunge) may exceed their firm pumping capacities. It is recommended that the City

review runtime records and monitor flows at these lift stations as development

progresses within their service areas.

The Hwy 13 Lift Station has a small wet well (6-foot diameter) relative to its capacity,

which causes the pumps to have short pumping cycles. Due to the short pumping

cycles, the pumps require frequent maintenance and replacement. Given the future

flows forecasted for this lift station’s service area, consideration should be given to

upsizing the lift station’s wet well in the future.

Trunk Sewer Analysis

The SewerCAD model was used to evaluate the estimated future peak hourly sanitary

flow for each trunk sanitary sewer (larger than 8-inch) in the system. These peak flows

and the subsequent residual capacities in each trunk are listed in Table 9-12 below.

All trunk sewers exhibit adequate capacity through full build out development. The

projected residual capacity of the future sanitary sewer system is shown in Figure 9-7.

Table 9-12. Trunk Sewer Capacity Analysis

Trunk Main

Location

Diameter

(in)

Capacity

(gpm)

Future Peak

Hourly Flow

(gpm)

Residual

Capacity (%)

W-15 15 1,095 331 70

W-14 33 6,337 514 92

W-13* 33 4,434 2,524 43

W-12* 33 4,118 2,803 32

W-11 15 1,321 317 76

W-10* 36 6,746 3,284 51

W-9 18 2,687 316 88

W-8 18 5,536 325 94

W-6 15 9,024 211 98

W-4 12 619 279 55

W-5* 36 5,184 4,630 11

E-17 10 609 213 65

E-16 15 2,673 282 89

E-9 12 639 454 29

E-7 18 2,033 610 70

E-5 12 856 712 17

E-8 15 1,381 403 71

E-6 12 1,113 614 45

E-4 10 580 162 72

E-1* 36 6,693 6,266 6


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* These trunks will convey the flow generated in SW-1, SW-2, and the CRWSD in

the future since those sub-districts will likely be rerouted to flow by gravity to the

Big Sky Lift Station. Note that these trunks are not currently conveying the flow

generated in those sub-districts.

It is recommended that the City reviews flows and capacities in three parts of

the trunk sanitary sewer system as development progresses: (1) the 36-inch

trunks immediately upstream of the MCES Lift Station, (2) the 21-inch trunks

immediately downstream of the Big Sky Lift Station, and (3) the 15-inch trunk

located downstream of the CR42 Lift Station.

MCES Interceptor Facility Forecasts

The projected sanitary flows to the MCES Meters and Interceptors that serve the City

of Savage are listed in Table 9-13 below. Note that these flow projections include only

the flow contributed from the City of Savage. Future flows to the Blue Lake WWTP

from the City of Savage may be eliminated if the City decides the reroute the flows

from SW-1 and SW-2 to the Big Sky Lift Station. If this were to occur, those flows

would then be conveyed to the Seneca WWTP in Eagan. Future flows in Table 9-13

reflect this scenario.

Table 9-13. Projected MCES Facility Flows

MCES Meter MCES

Interceptor MCES WWTP

Future Average

Flow

(MGD)

Future Peak

Hourly Flow

(MGD)

M404

(Prior Lake) 7120 Blue Lake WWTP 0 0

M405

(Burnsville) 3-BV-39 Seneca WWTP 0.252 0.932

M406 (MCES Lift

Station in Savage) L66, 8560 Seneca WWTP 3.470 9.022


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Figure 9-5: Future Sanitary Sewer Districts


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Figure 9-6: Future Sanitary Sewer System


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Figure 9-7: Future Residual Capacity


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INFLOW/INFILTRATION (I/I)

I/I Background

Inflow is clear water, typically stormwater, which enters the sewer system through

broken manhole covers, sewer cleanouts, sump pumps, foundation drains, and rain

leaders. Infiltration is water, typically groundwater, which leaks into the sewer system

through cracks in the sewer mains, laterals, joints, and manholes.

I/I consumes available capacity in the wastewater collection system and increases the

flow into treatment facilities. In extreme cases, the added flow can cause bypasses or

overflows of raw wastewater. This extra flow also requires a larger capacity in the

City’s collection and treatment components, which results in increased capital,

operation and maintenance, and replacement costs. As a sewer system ages and

deteriorates, I/I can become an increasing burden on a City’s system. Therefore, it is

imperative that I/I be reduced whenever it is cost effective to do so.

In 1993, the City of Savage commissioned an I/I Study. The study was completed and

adopted by the City Council in 1995. A complete study was forwarded to MCES

shortly after City Council adoption. The I/I Study found two main sources of I/I. One

source is the old sewer pipes in the Downtown District. The other source was

determined to be illegal sump pump connections. The report recommended

addressing the deficient sewer pipes in the Downtown District through an

Infrastructure Replacement Program and the illegal sump pump program through the

adoption of a “tough” sump pump ordinance and an aggressive inspection program.

A complete accounting of the I/I reduction activities completed by the City over the

last twenty years is provided in the I/I Reduction section that follows.


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The City of Savage prohibits the discharge of stormwater to the sanitary sewer system

and requires the disconnection of existing I/I sources per the City Code excerpted

below. The majority of sump pump connections have been eliminated through the

adoption of ordinance, extensive public relations campaigns, and comprehensive

inspection programs. The City requires sump pumps to be installed prior to final

occupancy, thereby assuring that the installation will be inspected by City staff.

§ 53.05 PROHIBITION OF CLEAN WATER DISCHARGES INTO THE SANITARY SEWER

SYSTEM.

…

(B) Definition and method. No water from any roof, surface, groundwater sump pump,

footing tile, swimming pool or other natural precipitation water shall be discharged into

the sanitary sewer system. Dwellings and other buildings and structures which require,

because of infiltration of water into basements, crawl spaces and the like, a sump pump

discharge system, shall have a permanently installed discharge line which shall not at

any time discharge water into the sanitary sewer system, except as provided herein. A

permanent installation shall be one which provides for year-round surface discharge

capability to the outside of the dwelling, building or structure, or is connected to the city

storm sewer. Permanently installed discharge lines discharging water to the surface

shall be terminated on private property prior to any curb, gutter, or street. A

permanent installation shall consist of a rigid discharge line without valving or quick

connections for altering the path of discharge, and if connections for altering the path

of discharge, and if connected to the city storm sewer line, include a check valve and an

air gap located in a small diameter structure as shown in the city’s standards plates.

The Utility Services Superintendent or his or her designated agent shall determine the

appropriate method for providing a permanent installation to avoid flooding of

adjacent properties, sidewalks, streets and the like. A permanent sump pump discharge

system may not create a public nuisance under §95.01(B) of the city code.

(C) Disconnection. Beginning April 1, 1996, any person, firm or corporation having a

roof surface, groundwater sump pump, footing tile or swimming pool, or unpolluted

industrial waste now connected and/or discharging into the sanitary sewer system shall

disconnect and/or remove same. Any disconnects or openings in the sanitary sewer

shall be closed or repaired in an effective, approved manner, as approved by the Utility

Services Superintendent or his or her designated agent.


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I/I Analysis

The sanitary sewer system currently consists of 129 miles of gravity main, fourteen (14)

lift stations, and 6.1 miles of forcemain. Approximately five percent of the residential

housing in the City was constructed before 1970. All homes in the City were inspected

in the late 1990s to eliminate illicit sump pump connections. I/I reduction activities are

discussed in greater detail in the following section.

The amount of clearwater flow within the City was estimated by calculating the

average annual and peak month I/I rates, equal to the average wastewater flow minus

the base wastewater flow, using data from 2013-2017. The average flow, both annual

and monthly, was calculated from MCES meter data. The peak month flow was

determined for each year from 2013-2017, and then those peak month flows were

averaged to give the value listed in Table 9-14. The base flow was approximated as

the lowest monthly average flow within each year.

Table 9-14. Estimated I/I Rate

Metershed M405 M406

Average Flow (MGD) 0.248 1.841

Peak Month Flow (MGD) 0.278 2.097

Base Flow (MGD) 0.232 1.713

Average Annual I/I Rate (MGD (%)) 0.016 (7%) 0.128 (7%)

Peak Month I/I Rate (MGD (%)) 0.046 (17%) 0.384 (17%)


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I/I Reduction

From 1995-2005, the City of Savage took the following corrective steps to address I/I

in the sewer system:

• In 1996, the City adopted a sump pump ordinance, as excerpted previously.

• In 1996, the City hired a consultant to inspect every home in Savage for sump

pump connections to the sanitary sewer system. The final report was

completed in 1997. The inspections identified several areas where the City

must install storm sewers or drain tiles to provide an outlet for sump pump

discharges prior to homeowner disconnections. Two projects were completed

in 1997/98 in which sump pump discharge lines were connected to the City’s

storm sewer system.

• In 1998, a feasibility report and planning study was completed for the

Downtown area (the Hamilton District). The City Council embarked on a

multi-year, phased project to replace all the infrastructure downtown and

provide development/redevelopment opportunities of the commercial

downtown area that started in 2000. All aging sanitary sewer pipes will be

replaced as part of this program and an extensive storm system installed, with

water quality ponding elements, to capture all surface runoff.

• An extensive public relations campaign was completed regarding sump

pumps, including newspaper articles, direct mailings, two public informational

meetings and an educational video that ran weekly on the City’s local cable

access channel.

• As part of the sump pump program, the City of Savage applied for and

received an MCES grant for I/I reduction and subsequently entered into an

agreement with MCES for follow-up inspections and monitoring of the

program results for five years.

• In October of 2005 the City had a study prepared evaluating I/I near Xenwood

Avenue/TH 13. In conjunction with the TH 13 Frontage Road project the City

abandoned a significant portion of the sewer main that was contributing to I/I

in this area.


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More recently, the City’s I/I reduction efforts have shifted to rehabilitation of the

collection system, both public and private. The I/I reduction projects completed in the

last ten years are listed in Table 9-15 below.

Table 9-15. I/I Projects Completed

Year Approximate Location(s) Description Cost

2009 Alabama Ave, Zarthan Ave Adjust SSMH Casting

Reconstruct SSMH $13,230.00

2010 Inglewood Ave, Lynn Ave,

Glenhurst Ave

Adjust SSMH Casting

Reconstruct SSMH $44,946.50

2011 Alabama Ave, Brunswick Ave,

Huntington Ave, 141st St Adjust SSMH Casting $39,655.00

2012

132nd St, 134th St, 135th St,

Natchez Ave, Ottawa Ave,

Monterrey Ave.

Adjust SSMH Casting

Repair SSMH

Replace Sewers and Services

Televise Sewers

$329,343.69

2013

Quentin Ave, Monterrey Ave,

Joppa Ave, Glenhurst Ave,

Dakota Ave

Adjust SSMH Casting

Repair SSMH


Televise Sewers

$335,426.62

2014 Connelly Pkwy Adjust SSMH Casting

Repair SSMH $10,560.00

2015 Quentin Ave, 139th St, 140th St

Adjust SSMH Casting

Repair SSMH


$68,051.00

2016 Connelly Pkwy, Boone Ave Adjust SSMH Casting

Repair SSMH $29,325.00

2017 136th St, 145th St, South Park Dr,

Zinran Ave

Adjust SSMH Casting

Repair SSMH

Seal SSMH Joints

$226,655.00

2018 Dufferin Dr, Ottawa Ave, River

Crossing, Vernon Ave

Adjust SSMH Casting

Seal SSMH Joints $164,508.32

Total $1,261,701.13

SSMH = sanitary sewer manhole


26

I/I Implementation

The City has invested approximately $126,000 annually in I/I reduction over the last

ten years and plans comparable investment going forward. Over the next ten (10)

years, the City plans to implement the sanitary sewer rehabilitation projects listed in

Table 9-16 below. The rehabilitation and replacement work that has been completed

over the last ten years has resulted in a reduction of I/I, and the City of Savage is

committed to further eliminating sources of I/I in its sanitary sewer system.

Table 9-16. I/I Implementation

Year Approximate Location(s) Description

2019 Glendale Rd, Bridgewater Dr, 150th

St, Hampshire Ave

Televise Sewers

Adjust SSMH Casting

Repair SSMH

Seal SSMH Joints


2020 Yosemite Ave, W Hidden Valley Dr,

Dufferin Dr

2021 137th St, 154th St, Aquila Ave

2022 South Park Dr, O’Connell Rd,

Kipling Ave, Joppa Ave

2023 Flag Ave, Eagle Creek Pkwy, Credit

View Dr, River Oak Dr, Allen Dr

2024 125th St, 126th St

2025 Carriage Hill Rd, Foxberry Rd,

Heatherton Ridge Dr

2026 Wyoming Ave, Preserve Tr,

Yosemite Ave, Woodhill Dr

2027 Hwy 101 Frontage Rd, Boone Ave,

126th St, Quentin Ave, 143rd St

2028 Taylor Dr, Quebec Ave, Nevada

Ave, Sumter Ave, Virginia Ave

SSMH = sanitary sewer manhole


27

PROPOSED IMPROVEMENTS

The sanitary sewer system will require trunk extensions to serve the remaining

unserved portions of the City. The estimated costs of these improvements, as well as

planned maintenance and rehabilitation work, are listed in Table 9-17 below. The

estimated costs are in 2018 dollars, include only trunk oversizing (the incremental cost

above 8-inch pipe), and include a construction contingency and indirect costs.

Table 9-17. Proposed Improvements

Year Description Estimated Cost

Annual I/I Reduction Approx. $126,000

TBD W-16 Trunk Main Extension $320,000



TBD Hwy 13 LS Wet Well Expansion $280,000

TBD 154th St Lift Station Abandonment $25,000

OUTCOMES

The analysis provided in this Comprehensive Sanitary Sewer Plan is intended to

provide the City of Savage and the Metropolitan Council assistance in planning for

wastewater collection and treatment. It is anticipated that the design criteria and flow

projections will be referenced for utility planning as development continues. Tables

and figures can be utilized to create budget-level estimates and schematic

representations of infrastructure improvements, while specific sizing and routing will

need to be determined during the design phase of individual projects.

Chapter 9 - Sanitary Sewer Plan

Documents

Transcript of Chapter 9 - Sanitary Sewer Plan